


Filling In

by orphan_account



Series: Making Do [2]
Category: Captain America (Movies), Marvel Cinematic Universe
Genre: Alpha Peggy Carter, Alpha/Beta/Omega Dynamics, Beta Bucky Barnes, Double Anal Penetration, Double Penetration, Implied/Referenced Rape/Non-con, Knotting, Mating Cycles/In Heat, Multi, Omega Steve Rogers, Threesome - F/M/M, Wartime
Language: English
Status: Completed
Published: 2014-12-01
Updated: 2014-12-01
Packaged: 2018-02-27 16:50:13
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 7,607
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2700239
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: <blockquote class="userstuff">
              <p>Bucky hurried through the unfamiliar streets, peering at house numbers and street names in the darkness as he tried to block out the waves of sensations crashing through him. He knew it wasn't far to Carter's place; had been past it with Steve already and had it pointed out to him on their way back to the barracks a few days ago. But everything was different and disorienting at night, and he still hadn't gotten used to the winding, haphazard layout of the city. London was nothing like New York, and although it usually took Bucky a lot to get lost, the combination of the dim light and the distracting surges of his bond-mate's heat were enough to make it damn hard to get where he needed to <i>go</i>, that was for sure.</p><p>(Sequel to <a href="http://archiveofourown.org/works/2499572">Just Make Do</a>.)</p>
            </blockquote>





	Filling In

**Author's Note:**

> Okay, so, essentially what happened, is: I planned out a whole plot following on from the last fic in this series, where a whole bunch of (mostly sad and awful) shit happens, and then skipped right to writing Peggy, Bucky and Steve having a threeway. So, there are references in here to things that I haven't written yet, sorry! We're out of chronological order! For the most part though, this is just shameless porn that stands on its own. 
> 
> There is one line that references sexual assault that occurred (to Steve) in the events that I haven't written about yet. Please bear that in mind before reading. Otherwise, things are mostly pretty nice. And hopefully self explanatory.

Bucky hurried through the unfamiliar streets, peering at house numbers and street names in the darkness as he tried to block out the waves of sensations crashing through him. He knew it wasn't far to Carter's place; had been past it with Steve already and had it pointed out to him on their way back to the barracks a few days ago. But everything was different and disorienting at night, and he still hadn't gotten used to the winding, haphazard layout of the city. London was nothing like New York, and although it usually took Bucky a lot to get lost, the combination of the dim light and the distracting surges of his bond-mate's heat were enough to make it damn hard to get where he needed to _go_ , that was for sure.

All these goddamn terrace houses looked the _same_. He knew that Carter's building had a deep navy blue door with a gold letter box, and vines covering the railings outside the upstairs window. But Christ, navy-blue didn't look all that different to dark green this time of night, and he wasn't even positive he was in the right street, regardless.

He peered at each house as he went by, running his hands through his hair in near panic. _Steve, goddammit,_ he thought as loudly as he could. _Just gimme something, anything. Street name, number. Anything._

But nothing came back from Steve's end of the bond except for that continuous feeling of scratching, bone deep _heat_ , and a continuous, desperate, wordless pleading. A pleading for Bucky to come back, back to the barracks, back to their room. Guilt stabbed through Bucky. He knew he shouldn't be away from his bond-mate when he was like this, not for long. But he needed Carter. He needed _help_.

Finally he stopped in the middle of the sidewalk, and just made a noise of frustration in the back of his throat, spinning on his heel. It had to be round here somewhere, he thought desperately. Unless he had made a wrong turn somewhere. Goddammit, Bucky had never had this much appreciation for good town planning in his life.

And then, like some sort of beacon of hope, a hall light switched on in one of the houses a little way down the road and the door swung open, sending a golden ray of light onto the stone pavement. It cut an angle through the darkness, and Bucky could see the light catching off the silk fabric of a night-robe as the woman came outside onto the front steps.

'Sargent Barnes?' Peggy asked, in confusion. 'I saw you from the window, what on earth are you doing out here?'

'Oh, thank Christ,' Bucky breathed, hurrying back down the street until he stepped into the light from her doorway. His stomach churning as another swell of Steve's heat crashed through him, he knew he must look a mess to her – his uniform hastily pulled on, hair wild. 'Ma'am,' he said quickly. 'I didn't want to disturb you--.'

She raised her eyebrow at him, looking down from her elevated spot on the steps, and leaned against the doorway, holding the front of her robe shut. 'But you thought you'd do it anyway?'

'It's Steve,' he explained. 'I ain't... He's gone into heat, is the thing.' He dropped his voice down low on the words, and saw her eyes widen, and her lips part as she sucked in a breath. 'Can I come in for a moment?'

Her expression tightened, and she nodded curtly. 'Yes.' She stepped aside, holding the door for him. 'I think you'd better.'

The inside of Carter's house was bare, but welcoming. It was clear she hadn't been in very long since she got back from the last tour. The side table next to the door had only an empty vase and a ceramic bowl with her keys sitting inside them. As Bucky came in the door, she crossed her arms and waited for him to close it behind him, before speaking.

'I was under the impression that you and Captain Rogers were bond-mates,' she commented, looking Bucky over shrewdly. 'So I'm afraid I don't quite understand why, if Steve is in heat, you are _here_ , chatting to me.'

Bucky let out a ragged breath, rubbing his palm over his eye. 'We are,' he said. He could feel Steve getting more and more panicked on his end of the bond. Shit, that wasn't good. He had never been very good at handling being alone while in heat, but it had to be worse, now. So much worse. 'But I... I ain't an alpha, you see? I know I--'

'You smell like an alpha,' she interjected, and then furrowed her eyebrows. He could see her nostrils flare a little, as confusion passed over her gaze. 'Or, actually...'

'Yeah, see? I'm just a beta. I know, it can be hard to tell.' He bit the inside of his cheek, trying not to say more. Whatever it was they had done to him at the HYDRA base, he didn't like to think about it. But he knew he just wasn’t quite right anymore. But he was still _him_ , he had to be. And it wasn't much different, not really. People had pegged him as an alpha often enough already, it was just a bit more... persistent, these days.

Peggy frowned. 'Wait, how are you two bonded?'

'Just are.' Bucky shrugged. 'But ma'am, you don't understand. It used to be... It was fine before. Before Steve became, you know, _this_. I could look after him alright. But now. He needs an alpha, Agent Carter. I ain't enough, not anymore.'

There was a long moment of silence, as Bucky let his gaze drift off to the door, lips twisting in concern. He knew he was asking a lot. He could feel Peggy's gaze on him, searching. They hadn't even had a conversation half this long, before now. She barely even glanced at him most of the time, her eyes only for Steve.

For a while, it had grated at Bucky; someone else hedging in on his territory. Worse still, since as an alpha, Carter would be perfectly in her rights to take what was his. As a non-breeding couple, his and Steve's bond wasn't legitimate and they still had to fight to hide it from most everyone, like they had to fight to hide Steve's omega status. But Peggy knew anyway – had known since before Steve went and got himself fucked with, apparently – and it soon became clear to Bucky that she respected their bond. Even if there was still a niggling line of cut competition between them, biological and unnecessary, Bucky had to admit that Peggy was alright.

She wouldn't take Steve from out under his nose. Not deliberately. Which was what made coming to ask her for this, for her help, all the harder.

But she just made a disapproving sound in her throat, and turned on her heel, walking briskly over to the stairs. 'I'll get dressed,' she said. 'How's he doing?'

'He'll be pissed as hell when he works out where I've gone,' Bucky answered with a humorless laugh, raising his voice as Peggy disappeared into her bedroom, leaving the door ajar. 'For now he's a bit too disoriented to know what's going on, though.'

'You shouldn't have left him,' she called back. He could hear the rustle of fabric as she dressed quickly, and sighing, Bucky fell back against the wall, scratching at his neck. He knew that, thank you, Agent Carter. But this wasn't like any of Steve's past heats. This wasn't even like that one heat after they had bonded that Bucky tried not to think about, ever. This was something else, entirely. The serum had changed Steve's body – everything about his biology – so much that Bucky had barely recognized the bond for a while after Steve had gone and recklessly volunteered himself for science, or whatever they called it. They were adjusting now, yeah. But heat was still a very different question.

Before, it had felt like crashing waves. Now, it felt like a seismic tidal bore, and Bucky could _feel_ Steve drowning. And he was helpless to save him.

'It's not me he needs,' he told Peggy, as she came out of the room wearing a long coat and heels. She tsk-ed him brusquely.

'You're his bond-mate,' she said. 'I'll help, if you are certain it's necessary. But it most certainly _is_ you that he needs with him.'

'Yeah,' Bucky muttered, following the alpha out the front door. She grabbed the keys and hurried quickly down the steps, her heels clicking on the stone. 'Sure.'

*

'You locked him in the room?' Peggy asked disbelievingly, as Bucky kicked the key out from under the mat outside the door. He looked at her sidelong.

'You wouldn't?' he asked. 'Hell, the rest of the barracks don't even know he's not an alpha, do they?'

Concern crossed Peggy's face, and Bucky knew exactly why. The scent of heat was so strong just here out in the hallway, and there were plenty of alphas in the barracks. A whole building full of alphas and betas, and one lone omega super-soldier going into heat. Bucky would know immediately if anything bad had happened, and it hadn't, not yet. But this situation just wasn't sustainable.

'We need to get him back to my house,' Peggy said, voice low.

But Bucky shook his head. 'Look, not sayin' I disagree, ma'am,' he said, fitting the key into the lock. 'But trust me, you'll see, we ain't getting him anywhe-- _mmphh_!'

Steve was on him the moment the door opened, a low noise starting up in the back of his throat between a whine and a growl, and Bucky was thankful for Peggy, who shuffled them both inside forcefully and locked the door behind them.

'I see what you mean,' she commented, taking the room in. The scent of heat was strong, so strong. It was enough that it made the air almost hard to breath, like syrup, and the bed was just an absolutely wrecked mess of slick soaked sheets.

'Fuck you, Bucky,' Steve groaned into his mouth.

Sighing, Bucky lifted up his hands to run them soothingly through his bond-mate's hair and down over his neck and shoulders as he guided them back to the bed. Steve was naked, naturally, shivering and flushed and slick. Through the bond, Bucky could feel the aching, hollow feeling that the omega was experiencing, having been left alone longer than, admittedly, Bucky should have left him. He was literally thirsting for touch. 'I'm sorry,' he murmured. He had only been gone, what, forty minutes? 'I'm so sorry, baby, I needed help.'

It had been too much.

'Get him onto the bed,' Peggy ordered from behind them, and Bucky felt Steve's attention shift even as he melted into Bucky's caressing touches. Bucky glanced at her out of the corner of his eyes. She was shrugging off her coat, placing it on the dresser, and wandered over to stroke her own hand through Steve's hair, nails scritching into his scalp like one might pet a cat. 'Barnes told me you needed some extra hands,' she told Steve, who was finally letting them both guide him down to sit on the mattress.

Steve huffed out an annoyed sound, but his gaze was taking on a dazed, dopey quality as Peggy petted him. Bucky could feel Steve's desperation slowly beginning to ebb into something manageable as he began to go boneless, sinking into the mattress. Bucky took a step backwards, letting Peggy work.

She was an alpha. She knew how to do this.

'Bucky's an idiot,' Steve moaned as he slumped down onto the pillows. Bucky snorted softly. No lies there. ' _Peggy_... You didn't have to come, I promise.'

'Are you okay with me helping out?' she asked him gently, and Bucky felt a stab of concern come through from Steve's end of the bond. He caught the omega's eyes, and smiled weakly, nodding.

'You don't have to worry about me,' he said, voice soft. 'I brought her here, didn't I?'

Steve let out a low whine in his throat. 'Why are you over there?' he asked, and Peggy glanced over her shoulder, frowning at Bucky.

'What _are_ you doing back there?' she asked. 'You have to stay with him, you know that.'

For a moment, Bucky opened his mouth and tried to shape silent words. He wanted to say something like, _But you're here now, he don't need me..._. But he knew it wasn't entirely true, as much as it felt that way. After a moment, he just nodded, ran his hands through his hair, and crawled up onto the bed to press a kiss into Steve's temple. 'I'm right here,' he murmured, and Steve let out a pleased hum.

'I nearly kicked down the door to come find you,' he groaned as Bucky kissed his way down his neck, and Peggy kept petting one hand through his hair, while the other began to trace it's way down his body. Bucky glanced at her. Despite the fact that she seemed to be treating this as the necessity it was, there was a definite upturn to her lips and look of suppressed excitement hiding under her professionalism as she stroked her fingers down over Steve's, admittedly glorious, abdominal muscles.

Bucky felt a twinge of jealousy settle in his chest, and Steve's neck twisted immediately to look at him. He keened out a pained noise, flailing uselessly with his hand to halfheartedly push Peggy's off his body. 'He doesn't like it,' he gasped to her, and Bucky shook his head quickly.

'No, no, Stevie, baby,' he said quickly, reaching out to grab Peggy's wrist. He looked at her apologetically. 'Let her. I'm fine, I promise.'

'Barnes...' Peggy said, voice low and laced with warning. 'Is this a good idea?'

Bucky nodded quickly, letting go of her hand and nudging Steve's jaw around to face him. 'Hey, hey sweetheart,' he said, looking into Steve's dazed, heat-addled eyes. 'You want Carter to fuck you, yeah? You wanna be knotted?'

Steve nodded, lip drawn between his teeth in concern. 'But, Bucky, you...'

'But I can't knot you, can I pal?'

'No, but we've always...'

'Yeah, but who went and got themselves biologically enhanced by the government, so that their heat is ten times stronger and I just can't fucking keep up, huh?'

Steve frowned. 'Yeah, alright, that's on me.'

Bucky glanced at Peggy. 'Ma'am?'

She nodded and stood up, reaching up to the top button of her dress. 'Look after him for a minute,' she said. 'I'm going to get undressed.'

Steve whined, writhing in discomfort on the bed as he watched her step away – but he reached up to hold the nape of Bucky's neck, holding him close. Bucky closed his eyes, just gently kissing Steve's skin and sliding his hand down his body towards his slick. 'She ain't leavin',' he told Steve, who just twisted his neck to bury his face in the pillow, and made vague, incomprehensible sounds.

Through the bond, Bucky could feel a general buzz of irritation coming from Steve from under the surface level sensations of craving and need and distressed desire. 'You sore at me?' he asked his bond-mate, slipping his fingers easily inside his slick hole and feeling out that one spot that always made Steve see stars.

Steve pushed back against Bucky's hand, let out a loud groan as Bucky crooked his fingers, and nodded. 'We, we are going to talk, talk l—later,' he panted out, and Bucky hooked his chin over the omega's shoulder as he fingered him. This was the big difference, Bucky thought, between Steve's heats before the serum, and what he was going through now. His mouth used to run off as ever – what he said might have made next to no sense and be mostly delirious rambling, but he would motormouth on like he was tryin' to start something anyway. But since this heat had come on earlier in the evening, Bucky noticed that he had gone the other direction, speaking only when he felt he absolutely needed to.

Glancing up, Bucky could see Peggy stripping down a few feet away, her dress pooling on the floor. She was watching them, with her lip tugged between her teeth and a soft look to her eyes. The front of the rayon slip she was wearing was tented obscenely, and just sheer enough that Bucky could make out the flushed head of her cock through the silken fabric.

'What're you lookin' at?' he groused, not liking the sympathetic expression in her eyes. It was one thing for _him_ to think he wasn't enough for Steve – it was another when others came to the same conclusion.

But she just quirked her lips up, and came back over to kneel on the bed, straddling Steve's body so that one shapely, bare leg was nestled between Steve's side and Bucky's hip. 'I can see what you were worried about,' she told Bucky. 'He'll definitely be a handful.'

'I'm right here,' Steve grumbled, arching up as Peggy dragged her nails lightly over his nipples. He let out a long keen, the hand that wasn't still gripped tight in Bucky's hair coming up to hold Peggy's waist. 'Don't, don't, don't talk 'bout me like I'm not.'

'Mmm, yeah,' Bucky said, still rubbing his fingers directly on Steve's prostate so that he was writhing, pushing back, his small, flush cock leaking onto his stomach. 'But we're not listening to you, because you're a babbler, punk.'

Steve whined, trembling around Bucky's clever fingers. But he was looking up at Peggy, not him, eyes dazed and reverent, and Bucky could feel desire surging even stronger through the bond. Slowly, Bucky began to remove his fingers, making eye contact with the alpha.

'He needs you,' he said to her quietly, even as Steve panted out; ' _You_ never _listen to me when I'm in he – eat_.' His voice cracked on the last word, pathetic whimpering noises coming out from his throat as he was left empty.

Peggy quirked an eyebrow. 'He needs both of us, I think,' she replied.

Twisting his neck to look at Bucky, Steve nodded in agreement. 'Don't go again?' he begged quietly, hand fumbling out to try to pull Bucky's fingers back towards his slick.

Bucky just rolled his eyes. Through the bond he could feel Steve's concern at being abandoned by his bond-mate, and that... that was just, ridiculous. 'Not going anywhere,' Bucky promised, but slowly pried his hand out from Steve's shaky grip. 'But Carter is going to take over on that bit, hey?'

'Oh,' Steve murmured, and smiled up at her. 'That's great. Thanks Peggy.'

She laughed softly, and shuffled back on the bed, rubbing at Steve's thighs to ground him. 'My pleasure, Steve,' she said, and glanced at Bucky. 'Can we move him around a bit, you think?'

Pressing a closed mouth kiss to Steve's forehead, and getting just a pleased noise in response, Bucky nodded. 'However you want us, doll,' he muttered; and before he knew it, he was sitting up against the thin pillows at the head of the bed, leaning against the wall, with Steve reclining back against him, legs in the air, and Peggy settling between them, her fingers coming out to tease at the omega's dripping entrance.

Bucky watched her closely. It was strange to see someone _else_ doing this to his bond-mate: almost disorienting, like he was caught in some strange dream. He could feel some part of the bond, both from Steve's end and his own, almost _tremoring_ with the feeling of wrongness of someone else doing it, but...

But while it felt disconcerting, it also didn't feel... _painful_ , like the last time. The last time Steve had been touched by an alpha, it had gone through the bond like a bolt of electricity, like something that burned and destroyed, and they had both felt scarred for the longest time after. With Peggy, it was nothing like that. If anything, it felt like the bond was stretching, shifting to accommodate something more.

Bucky wasn't bond compatible with Peggy, there was no doubt about that. But he could feel the slight tug from Steve's end towards her, like the pull of a weak magnet. He was already bonded, of course, so the pull amounted to very little, but still Bucky could feel it.

No one ever said anything about that, about meeting other potential bond-mates after you were already mated. Bucky had always just assumed it was impossible. Maybe it was. Maybe it was only their illegitimate bond, the bond that shouldn't be able to exist, that wasn't quite strong enough to hold off other suitors.

'Stop thinking, Bucky,' Steve chastised, his ankles hitching over Peggy's shoulders. She was still wearing her little slip, but it was hitched up to expose her flushed, hard cock. As she leaned forward, Bucky tried to avert his eyes from the swell of her breasts, and felt Steve let out a breathless laugh against him, hand coming up to stroke at his cheek. 'Such-- such a gentleman,' he chuckled, shifting against Bucky's body as Peggy's fingers teased their way inside him again.

'Shut up, you idiot,' Bucky murmured, blushing and looking down at his bond-mate's flushed, sweat-sheened body, rather than the beautiful alpha in bed with them. He just caught a short glimpse of Peggy's smirk as she looked up at their conversation.

'Bit late to be telling him to shut up,' she pointed out as she slowly pushed her fingers inside of Steve, stroking her cock with her other hand. The way Steve was arching his back and pushing down against her hand, keening in his throat, it was obvious that he wasn't going to put up with much more teasing.

Bucky rolled his eyes. 'Don't I know it.' He smiled down at Steve as his bond-mate tilted his head back on to look up at him, looking vaguely offended. God, he was heavy these days – but having him pressed up against his body like this was good. Close, reassuring. Necessary. Leaning forward a little, Bucky kissed his cheek, tightening his grip on Steve's waist possessively. 'S'okay,' he assured him, and Steve let out a low, broken whine when Peggy seemed to find that spot inside him that made him lose it.

'Please, I need-- I need--' he begged, tangling one hand in the front of Bucky's shirt, and reaching the other out towards Peggy pathetically. He screwed up his face, writing down onto Peggy's fingers wantonly. 'You guys are both assholes,' he added, panting and breathless. Bucky laughed, and caught the alpha's eye over Steve's shoulder. She was grinning at him, eyebrow raised.

'He's good to go,' he told her, nodding. 'Been ready for a while.'

' _Hours_ ,' Steve interjected.

'And you?' she asked, pulling her fingers out from Steve's slick hole and raising her voice over the unbidden cry he let out, squirming back against Bucky; who held him tighter and rocked his hips up against him from behind, through his uniform pants.

Bucky licked his lips, eyes dragging down the curves of Peggy's body and to her erection, peeking out from under the folds of her skirt. To his surprise, he had already noticed that she wasn't actually _that_ much bigger than him, in that department. It was almost enough to make him think that maybe he wasn't really all that inadequate compared to an alpha – if it weren't for the shape of the knot, just at the base of her cock. It wasn't swollen just yet. The bulb would expand enough to lock her and Steve together, but that would happen later – that would happen once she was already deep inside him, and that, _that_ was the important part. Giving Steve that feeling of real, _full_ , completeness that Bucky simply couldn't.

'Yeah,' he said to Peggy, tilting his head back a little against the headboard. Steve was making vague, persistent sounds of _want_ , and Bucky could feel his desire within himself, as well. He could feel that feeling of twitching, hollow emptiness. He could feel Steve's shaking need for it to just _go away_. 'Yeah, ma'am, he's all yours.'

Steve's fist clenched even tighter in the rough fabric of his shirt.

Peggy shifted forward, lining her cock up with Steve's slick entrance, and Bucky could feel it the moment she began to push inside. Not just from Steve's reaction (a sudden, full body tremor followed by a boneless slump of utter submission, and a long, quiet hum of pleasure), but also inside himself. He could feel the immediate, deep satisfaction; and it only grew stronger as she thrust deeper inside him, moving with small, easy rolls of her hips until she was seated entirely inside him. Bucky could _feel_ the fullness.

'Holy shit,' he commented, voice coming out rough with arousal, and Peggy caught his eye with a slightly surprised look. Steve let out a faint noise of amusement.

'Feels good, don't it, Buck?' he murmured, head tilting around a little and lips parting, damp and red, clearly in an invitation for Bucky to kiss him. Bucky dropped his head down to press their foreheads together, and panted as Peggy began to thrust with even, slow movements that barely pulled back out of Steve's body, instead just rolled in undulating movements of pleasure, like gently swelling waves.

Bucky knew that, because he could feel it too, by a degree of separation. Christ, he had been right to get Peggy on board, that was for sure. There was no _way_ that he could satisfy Steve like this, not anymore. _No way_.

'It's alright, Steve,' Peggy said, voice low and easy, as she moved inside the omega. Steve was falling apart quickly, his body going slack and malleable, but his hands tightening on Bucky's shirt and the noises coming out of his throat sounding simultaneously consumed by pleasure, and more than a little distressed.

Bucky furrowed his brow, kissing just at the line of Steve's eyebrow. His skin was warm with fever, damp with a sheen of sweat. Peggy's hands came up the flanks of his legs, red nails digging in just a little bit, and she blew a huff of air into her face. 'Rogers, stay with me,' she said sharply.

Steve shifted against Bucky's body, pushing down against Peggy's cock. Another noise came up from his throat, sounding completely involuntary and more like the creaking of a wire that was about to give, than anything. All that Bucky could feel through the bond was drowning pleasure and hazy fog.

'Hey, what's wrong?' he asked, nudging at Steve with his nose and wrapping his arms around the omega's broad chest, which was heaving, and flushed with arousal. Steve made no response, except to let out another unbidden keen and make another half-attempted movement to pull Peggy closer.

She glanced at Bucky, and shifted so that she was mostly lying forward on top of Steve, instead of kneeling up, her folded legs shifting further apart as she bent forward. One hand came up to brace on Bucky's arm, holding herself up just a little.

'What's wrong?' Bucky asked again, this time to her.

Peggy shook her head, laughing a little as Steve twisted his head away from Bucky to nuzzle at her hair, still making that distressed sound. His eyes were screwed up tight and cheeks flushed red.

'Shouldn't you be able to feel it?' she asked, a little dryly, voice tight from pleasure. She sighed when Bucky just shook his head, minute and confused. She took her hand off of Steve's thigh to stroke it through his damp hair. 'He's just uncomfortable, I think,' she said. 'Because it's not his bond-mate doing this for him.'

'Oh.' Bucky swallowed, flattening his palm over Steve's chest and rubbing as soothingly as he could. 'I, uh, thought that was just comin' from my end,' he admitted, with a quirk of the lips. He looked down at Steve, bumped him with his jaw pointedly. 'It's okay though, yeah? Lookit me, dumbass.'

'Love it,' Steve managed to grit out between his teeth. 'Love you. Love...'

'Don't get sappy on me now,' Bucky interjected, shooting Peggy an exaggerated long-suffering look. 'He's alright,' he told her. 'Same lump as usual.'

The corner of her lip quirked up in amusement, but the expression fell away quickly as her eyes drifted shut and her lips parted. She wet them, a quivering tremor of arousal passing through her body. ' _Steve_ ,' she moaned, and Bucky felt it before he knew what was happening.

He felt the feeling of fullness, of being stretched open; laid bare and just simply _whole_. Scrabbling for purchase, Steve let out another wrecked noise, and tugged blindly at Bucky, pulling him down into a kiss that was like he was trying to swallow him inside of himself.

' _Peg-- Peggy..._ ' Steve stammered against Bucky's lips, as they were locked together by the swell of the knot. ''M so full.'

'I know, I know,' she breathed into his neck, her hair pooling out over Steve's shoulders. The arch of her back rolled as he rocked inside him, pace picking up. 'You going to let go, Steve? Don't have to hold it in.'

Bucky hummed in agreement, kissing into Steve's mouth. His own arousal spiked through him almost painfully, but he could do little more than roll his hips up minutely, chasing pleasure he couldn't quite catch up to. 'Listen to the lady, Stevie,' he said encouragingly. 'Let go, yeah? I can feel that you're ready, c'mon.'

Steve nodded, but make a disagreeing noise at the same time. 'Don't wanna,' he panted, even as he held Peggy even closer. Her own thrusts were losing time, becoming erratic, and she was letting out soft, almost growling sounds into Steve's skin. 'Not, not without you.'

Bucky just sighed. 'I'm right here, right with you. Just let it out. Do it for me.'

But that seemed to annoy Steve, and he let go of Bucky's shirt to grab the back of his neck, almost a bit too hard. ' _No_ ,' he snapped. ''S gotta be together, Buck, or, or I don't think--'

'I can't--' Peggy interrupted, moaning deeply between them, clearly trying and failing to slow her movements. 'I'm sorry, I'm going to, Steve. I can't hold off, I--'

'S'okay, s'okay Peggy,' Steve answered, breathless; but her name became a drawn out, almost pained whine as she stilled and shuddered out her release inside him. Bucky could feel through the bond, feel Steve holding back from following suit – his heat clawing inside him, desperate for his own release.

'Goddammit, Stevie,' Bucky growled in frustration, dropping his head down onto the omega's shoulder. What was even the point of trying, really, when his mate was such a stubborn asshole?

'I'm sorry,' Peggy breathed shakily, lifting herself up a little on Steve's chest to look at Bucky. 'I shouldn't have--'

Bucky waved her off, shrugging the arm that she was still bracing herself on. 'Don't worry 'bout it,' he told her. 'This little punk is just bein' difficult.'

Steve groaned in objection, still rocking his hips around Peggy's cock. They were still knotted together; would be for a pretty long while yet. 'Want you,' he panted to Bucky, who grunted in reply.

'You agreed you wanted Carter,' he reminded his mate. 'And you goddamn know, you _know_ I'm not--'

'For fuck's sake, Bucky, shut up!' Steve snapped out, bitter irritation spiking from both ends of the bond, even through the fog of heat. With gritted teeth and clear effort, Steve kept talking. 'Want, want _both_ of you. Stop feeling sorry for yourself. So you're a beta, so what? I don't care. I don't care about no stupid knot.'

Bucky scowled, feeling embarrassed and guilty for quite literally trapping Peggy in the middle of their little domestic. 'Well, you obviously d--' he started, regardless, but Steve cut him off again.

'Don't tell me what I want!'

'I can read your goddamn mind, Steve!' he shot back.

'Well, not very well!' Steve bit back, and then cut his own words off breathlessly as Peggy suddenly pushed herself up on his chest, nails digging pointedly into the skin of his chest.

'That's enough!' she cut through in a sharp voice that made both of them fall immediately silent. The tone was all alpha, all command, and it was enough to cut right through Bucky's fight and shut him up – while for Steve, it took him one step further. Clearly unconsciously, he tilted his head back to expose the line of his neck in submission and let out a low, apologetic whine. She huffed out a breath. 'Better,' she said. 'Steve, I can see you're getting more talkative.'

'The, the knot,' Steve replied, a little hesitantly, like he wasn't sure he should answer. 'Clears my head.'

'Well, that's handy,' Peggy continued. 'Because we are going to be like this for a while yet.'

Steve nodded, head still resting back on Bucky's shoulder. 'I just want...'

'You just want your bond mate?' she asked, and he nodded again. Bucky swallowed, guilt twisting in his stomach. Had it been a mistake, bringing Peggy here?

'Steve...'

'Bucky, I want you to come inside me, please. I need to come, I need you _in_ me, I need--'

Bucky glanced down the bed. 'That spots kinda taken, buddy.'

Squirming, Steve keened, scrunching up his face. 'More,' he pleaded, and Bucky glanced up, eyes widening, and met Peggy's gaze.

'No...' he muttered, but there was a tug of amusement at the corner of Peggy's lips, a hint of challenge to her eyes.

'I bet he can take it,' she said consideringly. Bucky shook his head. God, how the hell did he end up in bed with _two_ reckless idiots?

'Uh huh, yeah,' Steve agreed. 'Both of you.'

Bucky closed his eyes, fighting back the feeling of hot arousal that shot through his body at the thought of Steve stretched open, filled with both his own and Peggy's dicks, her come already leaking out between them, mixing with his slick, easing the way. Christ. No, it was too much. Bucky groaned, hips canting up in the small space he had, with Steve and Peggy's combined weight resting on him.

'Okay, okay,' he pushed out between gritted teeth – not so much in agreement, but just. Just to try to fucking _think_. 'I... Ma'am?'

Peggy snorted. 'I think we're a bit past that, Barnes.'

'But, are you...?'

'It's what Steve needs,' she said simply. 'I think we should give him whatever he needs, don't you?'

'Yes, yes please,' Steve murmured vaguely; and Bucky rolled his eyes. Yeah, sure. But they had got by on making do before, hadn't they?

'You're very demanding,' he told Steve sternly, but felt a surge of warmth come through the bond as he slipped his hand down Steve's back to slide his fingers down to his hole, stretched tight around Peggy's knot. 'Can you take it?' he asked, nudging his fingers up against his entrance. It was a strange feeling, pushing up alongside Peggy's dick, and he felt her moving inside him, trying to tilt her hips back to give him more room. It wasn't much good, what with the way her knot was filling Steve up. They'd have to work around that.

'Can take anything,' Steve replied, pushing down against Bucky's fingers. But he didn't press them inside, instead withdrawing them with a long exhale of shaky breath.

'We gotta move,' he said. 'I gotta, I gotta get my pants off, yeah?'

Steve shook his head. 'Open,' he insisted, arching up his back to give Bucky more room. With a low groan, Peggy pushed herself up until she was kneeling again, rather than slumping over Steve's body, and helped him angle his body up a bit so that Bucky could reach down and pop the button on his fatigues, pressing open mouthed kisses into Steve's shoulder as he pulled out his erection. He could feel himself sweltering from the body heat radiating from the omega, and from the fact that he was still mostly clothed. But Steve didn't want him to move, so he wouldn't.

'We're gonna have to, to--' he started, reaching out to press his fingers against the stretched ring of muscle between them, carefully pushing a finger in alongside Peggy's cock. It was an odd sensation, feeling the way that her knot was stretching his bond-mate, and he heard Peggy hiss, slightly oversensitive. She was still hard, yeah, but she had come only a few minutes before. 'Gotta go slow,' he murmured, and both the alpha and omega nodded. All that Bucky was getting from Steve's end of the bond was just tight, hot, _burning_ pleasure.

Steve was so slick inside that he was practically _soaking_. Bucky let out a soft groan into his neck as he pressed his finger deeper in, trying to loosen Steve up – open him even further. It felt too good, just to know that he would be sliding in alongside Peggy soon. He could feel the way her cock twitched at the stimulation of having him fingering Steve open like this, knuckles sliding up past her knot.

'You alright?' he asked her, words coming out muffled against Steve's skin. He looked up at her under his eyelashes. Her face was screwed up, almost somewhere between pain and pleasure, but she nodded, a breath coming out as a soft moan.

'It feels good,' she assured him. 'Just, just a lot of... pressure.'

Steve just whined. 'Another finger.'

'Jesus Christ,' Bucky breathed out in exasperation, and Peggy laughed softly.

'Slow down, Steve,' she said, and the omega tilted his head back even further again, baring himself entirely.

'Need to come,' he keened, his voice low – clearly seeking permission from Peggy. Bucky quirked an eyebrow, pausing in his kisses to bite a soft mark into Steve's strong shoulder. Just a reminder _who_ was the bond-mate here. He felt contrite amusement echo back through the bond, and acquiescently, Bucky carefully pushed another finger inside Steve's slick channel.

He took it slow, gentle: and by the time he was pushing three fingers smoothly inside Steve alongside the alpha's cock, he could feel that Peggy was ready to go again, thrusting in a sort of alternating tandem with the moments of his fingers and letting out soft, breathless sounds that Steve was echoing in impatient whines. And although he didn't want to hurt Steve, no, not at _all_ , Bucky was starting to feel like if he held off a moment longer he might _die_.

Dimly, he hoped the walls in these barracks were thick. Real thick.

'Steve, are you read-' he started, but the omega cut him off with a low growl.

'If you ask me if I'm ready, I will walk out of here, Buck,' he replied sharply.

Bucky laughed. 'No you won't,' he countered, slowly sliding his fingers out of his bond-mate's wet heat, causing Steve to keen desperately, and Peggy to whimper. Bucky looked up with a surprised grin at the sound, raising his eyebrow at Peggy, who was flushed and moving in short, shallow thrusts, the swell of her breasts sheened with sweat. The rayon slip was clinging even tighter to her body, sticky from the heat that was cloying up the room, and she genuinely looked... wrecked. It was a look Bucky never would have expected to see on her – she always seemed so composed.

'Kiss him,' he told her breathlessly, as he angled his cock up against Steve's entrance, nudging the head up alongside Peggy's knot. She looked at him in surprise, mouth parted and slick from where she'd been licking at her lips. He nodded to her. 'Kiss him through it,' he told her. 'I wanna watch you. You want that, yeah, Steve?'

Steve let out a broken sound that could have meant anything – but the feeling of assent crackling through the bond burned right through to Bucky's core.

'He wants you to,' he told Peggy, whose eyes darkened with lust. She didn't reply, just leaned forward, pulling Steve into a deep, almost possessive kiss. If possible, Steve's body went even slacker, immediately, relaxing and welcoming Bucky into his body as he pushed into him.

Bucky groaned deep in his throat as Steve seemed to swallow him whole. It was something goddamn else, that's for sure – tighter, hotter than any of the times they'd done this before. He could feel the short thrusts of Peggy's cock sliding against his own, close fitting and pressed together so that her cock-head slid against his, their shafts side by side and just so, so, _so_ tight. He could feel Steve's slick and her come leaking out between them, easing the way and smearing Bucky's thighs, and –

And it was all overwhelmed by the sight of Steve opening his mouth and his body, and letting Peggy kiss into him like she owned him. Maybe like she owned _them_.

Bucky had to fight not to lose it right away.

'Jesus,' he murmured, kissing his way up Steve's neck to bite his ear. 'Jesus _Christ_.'

Through the heat, and the pleasure, and the submission, Bucky felt Steve flutter with affection through the bond. 'Feel good, Buck?' he asked into Peggy's mouth.

Bucky knew how it was feeling for _him_ : all complete, total fullness; relief cresting up to release. Bucky snorted. Steve would know how he was feeling. 'Know it does,' he murmured, and Steve chuckled. 'You gonna come for us this time?' he asked into the shell of Steve's ear, tilting his head a little to watch Peggy lick into his mouth as Steve moaned and nodded.

'Yes, yeah, yeah Buck. Peggy. Anything.'

He was close. Hell, he had been close since Peggy had been doing this to him on her own. Bucky could feel his body trembling over him, heat flushed and delirious. Over Steve's shoulder, Bucky locked eyes with Peggy.

She nodded, picking up the pace and thrusting deeper into Steve; quick, rolling movements that tore sudden groans from the omega and beta both. 'Let go, Steve,' she murmured into his mouth.

Matching Peggy's movements, Bucky started to slowly pick up the pace, squeezing his eyes shut against the suddenly overwhelming sensations – but hell, without seeing it, it was even worse. Everything honed in on the bond, and he could feel Peggy's lips against his ow-- no, Steve's; and he could feel his – no, _Steve's_ release barreling towards them. He could feel the tight, slick feeling of Steve around him, but he could also feel the aching, stretched fullness of being taken up by both his own and Peggy's cock. And the knot, the fucking _knot_ , that stretched him even more obscenely open, full.

And Steve was coming. He almost didn't seem to know what to do with his body as it hit him, scrabbling one hand up to tug into Bucky's hair, while the other just grasped loosely at the sticky bed sheets beside Bucky's hip. He keened, long and unsteady, and broke the kiss with Peggy to try and turn his head to capture his bond-mate's lips. The angle didn't quite work, and Peggy turned her head to follow, so that it just ended up as the three of them panting wetly into each others mouths, but that was, that was good. That was great. That was--

It was too much. Bucky couldn't hold on. His orgasm hit him like a punch to the gut, leaving him gasping almost in surprise and clenching his fingers against Steve's sweat-slick skin, and, surprisingly, Peggy's hand, which came down to tangle her fingers with his own.

Steve was like a sack of bricks as he came down from his release, slumping against Bucky and twisting his head around to mouth at his cheek and jawline so that Bucky was smiling indulgently through his orgasm, nearly laughing. 'S'the best, Buck,' he murmured.

Right. Bucky clenched his eyes shut again as everything became too much, and he made a half aborted, short thrust of his hips to chase the last moment of pleasure as come and slick slipped down over his cock. It was too much. The feeling of tightness, of being pressed up against Peggy's hard cock, which was still thrusting in rolling movements into Steve, but slower now – it was all much too much, almost painful, and Bucky found himself letting out a noise that just cracked in his throat, a soft _ah_ , and squeezed Peggy's hand tighter.

'Too much,' he gasped, and Peggy, bless her, pulled back on her next thrust to let him slip out of Steve's stretched hole. He let out a shaky breath, mouthing along the ridge of Steve's spine as he felt himself melting into the mattress.

But Steve, fucking _Steve_ and goddamn heat, was already squirming on top of him, pushing back against Peggy's slow thrusts. Bucky closed his eyes.

'You can't be ready to go again after all that?' he murmured, dancing the fingers of his free hand up Steve's sides to tweak at his nipple and feel him arch up.

Steve just groaned. 'Uh huh, mmhm, yeah,' he panted. 'S'okay Buck, you don't have to do anything.'

'I'll take him through it,' Peggy said, hips rolling a little faster. Bucky smiled.

'You'll stay, right?' he asked her.

She nodded, fingers tightening where they were tangled with his. She pressed a quick kiss to Steve's slack mouth. 'I'll stay,' she agreed.


End file.
